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641.
642.
ROBERT R. CHURCHILL 《Geographical review》2004,94(1):1-22
ABSTRACT. City maps are among the oldest and most popular forms of cartographic representation, yet urban cartography has received only limited scholarly attention. A review of the early history of city mapping suggests a progression of representational forms from profile to perspective to plan, a progression that parallels urban growth. The history of urban mapping reflects a desire to comprehend the geography of the city for reasons of curiosity and practical necessity, but the map also may become an icon that engenders a sense of pride and belonging, if not allegiance and control. An examination of Chicago maps indicates that, in addition to evolution in representational styles, the subjects of maps change to serve demands of the moment. City maps not only constitute a rich historical archive but also are dynamic agents in urban development. The urban landscape is shaped by cartographic vision. 相似文献
643.
利用Rayleigh波群速度资料反演得到中国大陆及其临近海域的(70°E-145°E,10°N-55°N)15-120s周期的群速度分布图像. 塔里木盆地在15s处清楚地显示为低速,在16-33s左右没有显示,但在36-5s显示为高速,说明塔里木盆地有较深的根. 青藏高原块体是44s至120s图像中最为突出的低速块体,南面与印度板块的分界线以及与北面的塔里木盆地、柴达木盆地的分界清晰,其块体中西部的速度低于东部. 泰国清迈附近存在一尺度为1000km左右的低速带,可能是青藏高原块体的物质向东南方向迁移造成上地幔物质上涌的结果. 南北地震带表现为强烈的速度梯度带,西面为低速,东面为高速. 中国南海的中央、日本海中央、菲律宾海表现为海洋性地壳. 菲律宾海的图像与地形及地震带完全吻合. 环绕菲律宾海及日本海存在400km左右宽的低速带,可能是岩浆活动带. 相似文献
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645.
Robert Lloyd 《The Professional geographer》2000,52(3):517-531
This paper argues cognitive mapping is a learning process that can be simulated by a self‐organizing neural network. The learning of city locations was considered in two studies. One study focused on the learning of city locations on four continents. Results indicated the neural network aligned the cities producing systematic errors similar to those in human cognitive maps. A second study had a neural network learn a biased sample of city locations in the United States. Results indicated a non‐linear relationship between cognitive and physical distances. Self‐organized cognitive maps naturally produce this non‐linear relationship when information from more than one scale is mapped into one space. 相似文献
646.
647.
地理空间数据的可视化 总被引:66,自引:3,他引:66
可视化是在数字化的背景中产生的,其作用是在人机交互的情况下发挥人脑有形象思维功能。地图本身是可视化的产品,并在发展过程中形成了一系列的理论与方法,这些都自然地会成了地理空间数据可视化技术的基础。地图学也因可视化方法的提出而获得新的动力。GIS也因可视化的支持而为研究者提供了保使逻辑思维与形象思维相结合的认识工具。 相似文献
648.
In this paper we apply a probabilistic methodology to map specific seismic hazard induced by the Vrancea Seismogenic Zone, which represents the uttermost earthquake danger to Romania as well as its surroundings. The procedure is especially suitable for the estimation of seismic hazard at an individual site, and seismic hazard maps can be created by applying it repeatedly to grid points covering larger areas. It allows the use of earthquake catalogues with incompletely reported historical and complete instrumental parts. When applying themethodology, special attention was given to the effect of hypocentral depth and the variation of attenuation according to azimuth. Hazard maps specifying a 10% chance of exceedance of the given peak ground acceleration value for an exposure time of 50 years were prepared for three different characteristic depths of earthquakes in the Vrancea area. These maps represent a new realistic contribution to the mitigation of the earthquake risk caused by the Vrancea Seismogenic Zone in terms of: (1) input data (consistent, reliable, and the most complete earthquake catalogue), (2) appropriate and specific attenuation relationships (considering both azimuthal and depth effects); and (3) a new and versatile methodology. 相似文献
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650.
This article recounts information gleaned from a case study of three indigenous tribes in Taiwan regarding the origin and nature of their spatial knowledge. Sketched mental maps and GIS 3D virtual environment (VE) are used by indigenous elders and hunters to delineate their traditional territories. Spatial components representing the predominant spatial elements are identified. Spatial structures used for locational positioning are analyzed, as are spatial reference systems for orientation and movement. The results show that spatial components are used for daily activities, as well as having historical and cultural meaning; a quadrant structure is used for spatial positioning; and instead of using the directional reference system of east, south, west, and north, these indigenous people rely on the orientation analogies of uphill, downhill, upstream, and downstream for direction. 相似文献